Four cycle engine for watercraft

A watercraft having a hull, an engine compartment in said hull, a propulsion unit carried by said hull for propelling said watercraft through a body of water, a four-cycle, internal combustion engine positioned within said engine compartment and comprising a cylinder block having at least one cylinder bore receiving a piston, a cylinder head affixed to said cylinder block and defining with said cylinder bore and said piston a combustion chamber, a crankcase affixed to said cylinder block and defining at least in part a crankcase chamber in which a crankshaft driven by said piston is journaled, a lubricating system for said engine comprising a lubricant tank fixed within said engine compartment in proximity to but spaced from said crankcase chamber and lubricant pump means for circulating lubricant from said lubricant tank to said engine and for returning lubricant from said engine to said lubricant tank, transmission means for driving said propulsion unit from said crankshaft, and a flywheel magneto driven off the front of said crankshaft, said lubricant tank being disposed above said flywheel magneto.

A watercraft having a hull, an engine compartment in said hull, a propulsion unit carried by said hull for propelling said watercraft through a body of water, a four-cycle, internal combustion engine positioned within said engine compartment and comprising a cylinder block having at least one cylinder bore receiving a piston, a cylinder head affixed to said cylinder block and defining with said cylinder bore and said piston a combustion chamber, a crankcase affixed to said cylinder block and defining at least in part a crankcase chamber in which a crankshaft driven by said piston is journaled, a lubricating system for said engine comprising a lubricant tank fixed within said engine compartment in proximity to but spaced from said crankcase chamber and lubricant pump means for circulating lubricant from said lubricant tank to said engine and for returning lubricant from said engine to said lubricant tank, and transmission means for driving said propulsion unit from said crankshaft, said lubricant tank being positioned to the rear of said engine.

A watercraft having a hull, an engine compartment in said hull, a propulsion unit carried by said hull for propelling said watercraft through a body of water, a four-cycle, internal combustion engine positioned within said engine compartment and comprising a cylinder block having at least one cylinder bore receiving a piston, a cylinder head affixed to said cylinder block and defining with said cylinder bore and said piston a combustion chamber, a crankcase affixed to said cylinder block and defining at least in part a crankcase chamber in which a crankshaft driven by said piston is journaled, a lubricating system for said engine comprising a lubricant tank fixed within said engine compartment in proximity to but spaced from said crankcase chamber and lubricant pump means for circulating lubricant from said lubricant tank to said engine and for returning lubricant from said engine to said lubricant tank, and transmission means for driving said propulsion unit from said crankshaft, said lubricant tank is disposed on a side of the engine.

A watercraft having a hull, an engine compartment in said hull, a propulsion unit carried by said hull for propelling said watercraft through a body of water, a four-cycle, internal combustion engine positioned within said engine compartment and comprising a cylinder block having at least one cylinder bore receiving a piston, a cylinder head affixed to said cylinder block and defining with said cylinder bore and said piston a combustion chamber, a crankcase affixed to said cylinder block and defining at least in part a crankcase chamber in which a crankshaft driven by said piston is journaled, a lubricating system for said engine comprising a lubricant tank fixed within said engine compartment in proximity to but spaced from said crankcase chamber and lubricant pump means for circulating lubricant from said lubricant tank to said engine and for returning lubricant from said engine to said lubricant tank, and transmission means for driving said propulsion unit from said crankshaft, said hull having an upper deck portion that tapers generally inwardly in an upward direction, said cylinder head being disposed in the upwardly tapering portion of the hull, said upwardly tapering portion of said hull defining in part a passengers' area for the hull.

A watercraft having a hull, an engine compartment in said hull, a propulsion unit carried by said hull for propelling said watercraft through a body of water, a four cycle internal combustion engine positioned within said engine compartment and comprising a cylinder block having at least one cylinder bore receiving a piston, a cylinder head affixed to said cylinder block and defining with said cylinder bore and said piston a combustion chamber, a crankcase affixed to said cylinder block in defining at least a crankcase chamber in which a crankshaft driven by said piston is journaled, an induction system formed on one side of said cylinder head for delivering a fuel air charge to said combustion chamber, an exhaust system formed on the other side of said cylinder head for exhausting burnt combustion products from said combustion chamber, position responsive valve means in at least one of said systems for precluding the flow of water into said combustion chamber through said system, and transmission means for driving said propulsion unit from said crankshaft.

A watercraft having a hull, an engine compartment in said hull, a propulsion unit carried by said hull for propelling said watercraft through a body of water, a four cycle internal combustion engine positioned within said engine compartment and comprising a cylinder block having at least one cylinder bore receiving a piston, a cylinder head affixed to said cylinder block and defining with said cylinder bore and said piston a combustion chamber, a crankcase affixed to said cylinder block and defining at least in part a crankcase chamber in which a crankshaft driven by said piston is journaled, an intake passage formed in said cylinder head on one side thereof and communicating with said combustion chamber, said intake passage being formed in part by an inlet opening, an air inlet device for collecting atmospheric air and delivering the air to said air inlet opening, said air inlet device comprising an outer housing having a discharge opening affixed in registry with said air inlet opening for delivering air thereto, an inlet opening in said outer housing for inducting atmospheric air from within said engine compartment, check valve means for closing said inlet opening when said hull becomes at least partially inverted for precluding water from entering said engine through said induction system, and transmission means for driving said propulsion unit from said crankshaft.